Vortex flowmeter VT00 liquid gas steam
Vortex Flowmeter VT00 No moving parts and reliable stainless steel structure Optimum measuring process reliability enabled by Digital Signal Processing (DSP) Measuring accuracy: ±1.0% Measurable medium: liquid, gas and steam VT00 is fitted with HART communication High working pressure, 42MPa (.) Output: 4-20mA analog signal & configurable pulse output Optional double sensors design with higher stability and reliability 1
Technical parameter Item VT00 Fig.1 Typical Diameter Nominal pressure Fluid temperature Sensor design Body material Accuracy Repeatability Flow Range Converter type Communication Wafer DN15~DN, Flange DN15~DN600, Insertion >= DN (1.6, 2.0, 2.5, 4.0, 5.0, 6.4) MPa. Other special pressure classes upon request Standard(-~+120), M-tem(-~+250), H-tem(-~+320) Single sensor or double sensors SS304, 316L, HC and other materials upon request ±1.0% < 0.33% 1:10~1:20 Compact & Remote HART Protocol Display T/P compensation Supply power LCD In preparation 15~28 V DC Output Current:4-20mA PulseVoltage : L<1V, H 5V Battery power Linear rectification Low flow cut-off Ex-Design Protection Class Applicable medium Ambient conditions Optional Available Available Ex ia II CT5,Ex d II CT5 IP Gas, liquid, steam Ambient temperature: (-~+60) Relative humidity: 5%~90% Atmospheric pressure: (86~106)kPa 2
Measuring principle The vortex flowmeter is used for measuring the flow velocity vof gases and liquids in pipelines flowing full. The measuring Principle is based on the development of a Karman vortex shedding street in the wake of a body built in the pipeline. The periodic shedding of eddies occurs first from one side and then from the other side of a bluff body (vortex-shedding -body) installed perpendicular to the pipe axis. Vortex shedding generates a so-called Karman vortex street with alternating pressure conditions whose frequency is proportional to the flow velocity. (Fig.2) Fig.2 The vortex shedding frequency f is proportional to flow velocity v and inversely proportional to the width of the shedder d: f = St v / d St, the Strouhal Number, is a dimensionless quantity. If the geometrical shape and dimension of shedder are designed appropriately, St is a constant over the wide range of Reynolds number Re (Figure 3). Re = v D / υ υ: Kenematic viscosity of fluid D: Meter body diameter Strouhal number St Fig.3 The vortex shedding frequency used to measure the flowrate is only a function of the flow velocity regardless of fluid density and viscosity. The pressure pulsation generating with vortex shedding will be detected by the Piezo-Sensor and converted into pulse signal corresponding to the vortex frequency in the test circuit, and the signal converter will convert this pulse signal into 4-20 ma normalized current signal and output it. 3
Flowmeter Size Selection The flowmeter size is determined from the imum operating flowrate Q V. To achieve the imum flow range, this value should not be less than one half of the imum flowrate for the meter size (RangeMax), but can be selected as low as 0.15 RangeMax. The start of the linear flow range is a function of the Reynolds Number. If the flowrate to be measured is specified as normal flowrate, (normal conditions: 0 C, 1013 mbar) or as mass flowrate, the values must first be converted to actual flowrate values at operating conditions and then the appropriate meter size can be selected from the Flow Range Tables (Tbls. 1, 2, 3). 1. Convert normal density ( ρn ) --> operating density ( ρ ) 1,013 + p 273 ρ = ρ n ------------------------ 1,013 273 ------------------- + T ρ = Operating density [kg/m 3 ] ρ N = Normal density [kg/m 3 ] p = Operating pressure [bar] T = Operating temperature [ C] Q V = Operating flowrate [m 3 /h] Q n = Normal flowrate [m 3 /h] Q m = Mass flowrate [kg/h] η = Dynamic viscosity [Pas] ν = Kinematic viscosity [m 2 /s] 2. Convert to flowrate at operating conditions (Q V ) a) starting with normal flowrate (Q n ) --> ρn Q V Q n ------ ρ Q 1,013 273 + T = = n ------------------------ ------------------- 1,013 + p 273 b) starting with Mass flowrate (Q m ) --> Q Q m V = --------- ρ 3. Dynamic viscosity ( η ) --> kinematic viscosity ( ν ) η ν = -- ρ 0 DN DN250 DN DN150 DN DN80 Q V min [m 3 /h] 10 DN25 DN50 DN DN15 1 0.1 0.1 1 10 ν [10-6 m 2 /s = cst] Fig. 4: Minimum Flowrate, Liquids as a Function of the Kinematic Viscosity 4
Flow Ranges, Liquids Meter DIN ANSI Size Q V min 1) RangeMax Frequency Q V min 1) RangeMax Frequency [m 3 /h] [m 3 /h] [Hz] [m 3 /h] [m 3 /h] [Hz] DN Inch Std. HT at Q v Std. HT at Q v 15 1/2 0.5-6 370 0.5-5.5 450 25 1 1.6 3.6 18 2 1.6 3.6 18 0 1-1/ 2.4 9.6 48 190 2.5 9.6 48 270 2 50 2 3 14 70 1 3 13 66 176 80 3 10 34 170 102 10 32 160 128 4 10 54 270 72 12 43 216 75 150 6 30 126 630 50 33 106 530 50 8 70 220 1 45 70 187 935 250 10 70 3 1700 29 82 289 1445 36 12 135 480 20 26 135 8 20 23 Tbl. 1: Flow Ranges, Liquids at 20 C, 1013 mbar, ρ = 998 kg/m 3 ) 1) Std. 280 C Version / HT = High temperature design (f = 0 C Pressure Drop, Liquids See Fig. 5 for water (20 C, 1013 mbar, ρ = 998 kg/m 3 ). For other densities ( ρ ) the pressure drop can be calculated using the following equation: ρ p' = --------- p 998 Static Overpressure, Liquids To avoid cavitation when metering liquids a positive static pressure (back pressure) is required downstream from the flowmeter. The required pressure can be calculated using the following equation: p 2 1.3 x p vapor + 2.6 x p' p 2 = p vapor = p' positive downsteam static pressure [mbar] vapor pressure of fluid at the operating temperature [mbar] = pressure drop, fluid [mbar] Example for liquids: Find the flowmeter size for metering 55 m 3 /h liquid with a density of 850 kg/m 3 and a kinematic viscosity of 2 cst = (2 x 10-6 m 2 /s). 1. Q V =. 55 m 3 /h --> DN50[2 ] (per Tbl. 1): Q V = 70 m 3 /h 2. Flow range start, linear, at 2 cst, (from Fig. 5): Q V min = 6 m 3 /h 3. Press. drop (Q v = 55 m 3 /h) at ρ= 850 kg/m 3 : p' = 425 mbar p' = Pressure drop fluid [mbar] p = Pressure drop water [mbar] (from Fig. 5) 0 Example 425 mbar p [mbar] DN 15 DN 25 DN DN 50 DN 80 DN DN DN 250 DN 150 DN 10 1 0.1 1 10 0 00 Q V [m 3 /h] 55 m 3 /h Fig. 5: Pressure Drop, Water (20 C, 1013 mbar, ρ = 998 kg/m 3 ), DIN-Design 5
Flow Ranges, Gas/Steam Meter DIN ANSI Size Q V min 1) RangeMax Frequency Q V min 1) RangeMax Frequency [m 3 /h] [m 3 /h] [Hz] [m 3 /h] [m 3 /h] [Hz] DN Inch Std. HT at Q v Std. HT at Q v 15 1/2 4-24 1520 5-22 1980 25 1 15 30 150 20 12 16 82 1850 1-1/ 30 78 390 1550 21 68 3 1370 2 50 2 500 1030 43 90 450 1180 80 3 2 1 700 78 190 950 780 4 150 380 1900 500 120 360 1800 635 150 6 900 4500 360 260 810 50 5 8 430 1600 8000 285 420 1360 6800 2 250 10 810 2800 260 820 20 10 225 12 1410 00 00 217 1 30 17000 195 Tbl. 2: Flow Ranges, Gases at ρ = 1.2 kg/m 3 ) 1) Std. 280 C Version / HT = High temperature design (f = 0 C Example for Gases: Find the flowmeter size for metering 25 m 3 /h (q n ) CO 2 -Gas; Temp. = 85 C, Press. = 5 bar a. For details see Page 5 Flowmeter Size Selection ρ = 1.97 kg/m 3 n (CO 2 ) 1. Convert ρ --> : =7.4 kg/m 3 n ρ ρ 2. Convert m 3 /h (q n ) --> m 3 /h (q v ): Q V = 676 m 3 /h (q v ) --> Selection : DN 80[3 ] (Q V = 1 m 3 /h) (q v ) 3. Pressure drop at ρ= 7.4 kg/m 3 : p' = mbar 4. Flow range start at ρ = 7.4 kg/m 3 (from Fig. 7): Q V min = 45m 3 /h, Convert m 3 /h (q v ) --> m 3 /h (q n ): Q V min = 169 m 3 /h (q n ) Pressure Drop, Gas/Steam See Fig. 8 for air (at 20 C, 1013 mbar, ρ = 1.2 kg/m 3 ) For other fluid densities the pressure drop can be calculated using the following equation: ρ p' = -------- p 1,2 p' = Pressure drop fluid [mbar] p = Pressure drop air [mbar] (from Fig. 8) Normal Densities of Various Gases: Gas Normal Density [kg/m 3 ] Acetylene 1.172 Air 1.290 Ammonia 0.771 Argon 1.780 Butane 2.700 Carbon dioxide 1.970 Carbon monoxide 1.250 Ethan 1.350 Ethylene 1.260 Hydrogen 0.0899 Methane 0.717 Natural gas 0.828 Neon 0.890 Nitrogen 1.250 Oxygen 1.430 Propane 2.020 Propylene 1.915 00.0 0.0 DN DN250 Q V min [m 3 /h].0 DN DN150 DN DN80 DN50 DN 10.0 DN25 DN15 1.0 0.10 1.00 10.00.00 ρ [kg/m 3 ] Fig. 6: Minimum Flowrates, Gas/Steam as a Function of the Fluid Density, DIN-Design (280 C) 6
00.0 0.0 DN DN250 DN DN150 Q V min [m 3 /h].0 DN DN80 DN50 DN DN25 10.0 1.0 0.10 1.00 10.00.00 ρ [kg/m 3 ] Fig. 7: Minimum Flowrates, Gas/Steam as a Function of the Fluid Density, DIN-Design (HT).00 10.00 p [mbar] DN15 DN25 DN50 DN DN80 DN DN150 DN DN250 DN 1.00 0.10 1.0 10.0.0 0.0 00.0 000.0 Q V [m 3 /h] Fig. 8: Pressure Drop, Air (20 C, 1013 mbar, = 1.2 kg/m 3 ), DIN-Design 7
Flowrates Saturated Steam [kg/h] Example for Saturated Steam: Find the flow range for DN 50 [2 ] at 7 bar (a). --> from Tbl. 3: DN 50[2 ]: 101-1835 kg/h Additional information: Sat. steam temp.= 1 C Sat. steam dens.= 3.67 kg/m 3 p[bar a] Meter Size 1 1.5 2 3 4 5 6 7 8 9 10 12 15 25 30 35 45 50 Inch DN 1/2 15 min 2 14 3 21 5 27 7 8 52 9 64 9 76 10 88 11 11 112 12 124 13 147 14 182 21 25 360 29 420 33 480 38 544 42 609 1 25 min 9 89 13 129 17 170 25 248 29 324 32 1 35 476 38 551 624 43 699 45 773 49 920 54 11 78 1875 94 2250 109 2625 125 0 141 31 158 3804 1-1/2 min 18 230 26 335 34 441 50 644 58 842 64 1041 70 1236 76 1431 80 1622 85 1817 89 9 99 2391 122 2964 201 4875 241 5850 282 6825 322 7800 3 8841 8 9890 2 50 min 24 295 34 430 45 5 66 825 77 1080 86 1335 94 1585 101 1835 107 2080 114 2330 119 2575 130 30 145 3800 208 6250 249 7500 291 8750 333 00 377 11335 422 12680 3 80 min 59 708 86 1032 113 1356 1 1980 193 2592 215 3204 234 3804 252 44 268 4992 284 5592 298 6180 329 7356 8 9120 671 15000 805 18000 939 20 1073 1217 27204 1361 30432 4 min 89 1121 129 1634 170 2147 248 3135 290 4104 322 5073 361 6023 418 6973 474 7904 531 8854 586 9785 698 11647 8 144 1423 23750 1708 28500 1992 33250 2277 38000 2581 43073 2887 48184 6 150 min 177 25 258 3870 339 5085 495 7425 580 9720 644 12015 722 142 836 115 947 18720 1061 20970 1173 23175 1396 27585 1730 34 2846 56250 3415 67500 3984 78750 4554 90000 5162 102015 5774 114120 8 min 254 4720 370 6880 486 90 710 13 863 17280 1067 21360 1267 25360 1467 29360 1663 33280 1863 37280 2058 41 2450 490 3038 60800 4996 000 5995 6995 0 7994 160000 9061 181360 10136 202880 10 250 min 478 8260 697 120 915 15820 1337 23 15 302 17 37380 1949 44380 2256 51380 2557 582 28 2 3166 72 3768 85820 4672 1060 7684 175000 9221 200 245000 10758 12295 280000 317380 13936 3550 15590 12 min 832 11800 1213 17 1593 22600 2327 30 2724 43 3092 530 3 630 3551 730 3780 83 01 93 4269 100 5081 122600 6 150 250000 10361 000 12434 350000 14506 178 0000 4530 18791 507 21021 Density ρ sat [kg/m 3 ] 0.59 0.86 1.13 1. 2.16 2.67 3.17 3.67 4.16 4.66 5.15 6.13 7.60 12.50 15.00 17.50 20.00 22.67 25.36 Temp. Tsat [ C] 99.6 111.4 120 133 144 152 159 1 170 175 180 188 198 224 234 242 250 258 264 Tbl. 3: Saturated Steam Flow Ranges, DIN-Design 8
Ordering Selection of Vortex Flowmeter Order series VT Converter type 4 Type of connection Wafer (DN15~DN) 0 Flange (DN15~DN600) 1 Insertion ( DN350) 2 Type of converter Compact 0 Remote 1 Measuring medium Liquid 0 Gas 1 Steam 2 Materials SS304 316L HC Others Meter Size DN15 15 DN20 20 DN25 25 DN DN50 50 DN80 80 DN 1H DN125 1T DN150 1F DN 2H DN250 2F DN... DN800 3H... 8H Pressure Rating PN16 PN20 PN25 PN PN63 PN 150LB LB 600LB Others Probe type Standard (-~+120) 0 High temperature (-~+250) 1 Super temperature (-~+320) 2 Sealing Graphite 0 PTFE 1 Others 9 Explosion proof None Exia ia II II CT5 CT5 Ex d II CT5 HART None 0 Yes 1 A B C M B L C D E F G K N P A B C 9
Profile and installing dimension Flange connection (mm) DN 15 20 25 50 80 125 150 250 PN 16/ 16/ 16/ 16/25 16/25 16/25 L 250 250 350 450 500 H 3 350 3 375 390 0 425 450 475 d 15 20 25 50 80 125 150 250 D 95 105 115 150 1 220/235 250/270 285/ 3/360 5/425 460/485 k 75 85 110 125 160 180/190 210/220 2/250 295/310 355/370 410/430 d1 14 14 14 18 18 18 18/22 18/26 22/26 22/26 26/30 26/30 N 4 4 4 4 4 8 8 8 8 12 12 12/16 b 14 16 16 18 20 24 22/24 22/26 24/28 24/30 26/32 28/34 DN PN 15 25 20 25 25 25 25 50 25 80 25 25 125 25 150 25 25 250 25 25 L 120 H 310 310 310 315 320 320 330 345 360 0 425 460 D 55 55 55 85 130 150 175 250 350 d Wafer connection (mm) 15 20 25 50 80 125 150 250 10 FISHERMETER
Installation The installation site and fixing manner of flowmeter will have a direct impact on its application. Incorrect installation will influence the measuring accuracy and the service life of the flowmeter, and even cause permanent damage to it, so the following items shall be referred during the installation. Inlet and outlet sections The installation of flowmeter shall satisfy the minimum requirements for the inlet and outlet straight section as shown Figure 9, or it will have a serious impact on the measuring accuracy or even on normal function of flowmeter. Figure 9 Length of inlet and outlet straight section (D: The nominal internal diameter of the meter) Installation for high fluid temperatures When the temperature of medium in the horizontal pipe is above 180, it is recommended that the remote type of flowmeter or side mounting be chosen, that is to say, the head of flowmeter is not on the top of the pipe, because high temperature may damage the electronic circuit in signal converter. Correct installation manner is as shown in Fig.10 Fig.10: Installation for high fluid temperatures (Temperature 180 ). Fig.11: Low installation shall be avoided for steam measurement Installation for steam measurement When the measured medium is saturated steam or humid gas, the flowmeter shall not be installed at the lowest part of pipe line (Fig.11), because the steam may condense into liquid at the lower part of pipe line, causing coexisting of water and steam, which may result in failure in performance of flowmeter and greater measuring errors. In addition, when the steam device is being opened, water hammer may appear at the lower part of pipe line. 11
Installation for liquid measurement When the measured medium is liquid, the liquid shall be full of the pipe, and it is better to make the liquid flow from a lower position to a higher or flow horizontally. The flowmeter shall not be installed at the highest part of pipe line (Fig.12), because the air bubbles may gather there and cause a serious impact on the measuring accuracy. If the pipe is vertical, the liquid shall not flow from up to down (Fig.13), or the pipe will not be full, which may seriously influence the measuring accuracy and cause failure in performance of flowmeter. Fig.12: High installation shall be avoided for liquid measurement Fig.13: Up-to-down flow shall be avoided for installation of vertical pipe line Thickness of thermal insulation layer If the pipe line needs to be kept warm, the thickness of thermal insulation layer covering the instrument shall not exceed 50 mm (Figure 14). The excessive thickness may cause a rise in temperature of signal converter which leads to a damage. Fig.14: Thickness of thermal insulation layer Fig.15:Required distance forflowmeter maintenance Service clearance More than mm clear space for mounting, dismounting and maintenance shall be allowed at the top of flowmeter during installation (Figure 15). Installation of Remote type flowmter The installation of separate flowmeter body is identical to that of compact flowmeter. The signal converter must be firmly fixed on the wall or in the cabinet. The longest transmission distance between the signal converter and primary body is 10 meters, and the connecting cable is two-core shielded cable. The shorter the signal transmission distance is, the less the interference. So it is needed to shorten the cable length according to actual need and cut the excessive cable. The unamplified signals from the transducer to signal converter may be easily interfered during transmission, so care must be taken to connect wires and the shielding layer shall be grounded reliably at the same place where the power is grounded. After grounding, the cable shall be fixed and better in the special cable trunk (Figure 16). 12
Precaution Try to avoid vibration, and rubber the support or connect by the hose if necessary. If the pressure fluctuation occurs when there is no flow in a long pipe, a gate valve is needed to be installed before and after the flowmeter. If water is contained in the steam or steam in water, a water separator shall be equipped. Installations for wafer type, flange connection and insertion type are separately as shown in Figure 17, 18 and 19. Fig.16: Remote type Fig.17: Wafer type Fig.18: Flange connection Fig.19: Insertion type 13
Contact us Once a quotation inquiry is received, a regional sales representative will contact you within 24 to 48 hours. International Sales Department Tel: +86-10-8483 3261 +86-10-8483 3671 Fax: +86-10-8482 9367 +86-10-8483 3673 E-mail:sales@fishermeter.com Technical Service Tel; +86-10-8947 8461-605 / 606 +86-10-8947 8421-605 / 606 Fax: +86-10-8947 8461-607 +86-10-8947 8421-607 E-mail:service@fishermeter.com Office Address Beijing Fishermeter Instrument Co., Ltd. Post Code: 107 Room 1204, B Block Fortune Center, Tianlang Garden, Beiyuan Road, Chaoyang District, Beijing, China. (107) http://www.fishermeter.com/english Factory Address 1 st building, Mauhwa Industry Park 1st block, Caida 3rd street, Caiyuan Industry Park, Nancaizhen Town, Shunyi District, Beijing, China. 14